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  • 1.
    Almudhari, Haider
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Effektivisering av materialhantering gällande plåtrullar i SSAB:s Stålhamn: En fallstudie på Oxelösunds Hamn AB2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Idag befinner sig produktionsföretag under konkurrenskraftiga och snabba förändringar i en global marknad. Det utmanar företag som jobbar med materialtillverkning och distributionsnät på en global nivå till att ständigt förbättra deras verksamhet. Aktörerna som verkar inom en och samma supply chain bör enas för att kunna bli konkurrenskraftiga och flexibla, som respons på globaliseringen. Genom att företag skapar gemensamma mål, delar information, risker och vinster kan alla aktörer inom kedjan gynnas.

    Denna fallstudie har genomförts på en av Oxelösunds Hamns verksamheter, nämligen SSAB:s Stålhamn, som de driver åt SSAB i Oxelösund kommun. Stålhamnen har en viktig roll i SSAB:s supply chain eftersom den agerar som SSAB:s skeppningshamn där material som kommer från SSAB i Borlänge och Oxelösund lagras tills de ska skeppas vidare till andra hamnar i världen. Idag upplever Oxelösunds Hamn ineffektiv information- och materialflöde inom Stålhamnens verksamhet.

    Syftet med studien är att undersöka materialhantering i form av vilka transport- och lagringsmetoder som sker inne i en av Stålhamnens verksamheter, Coilsterminalen. Därefter klargörs vilka slöserier som finns samt hitta förbättringar för att effektivisera information- och materialflödet vid hanteringar av plåtrullar i Coilsterminalen.

    Studien har primärt genomförts genom observationer, ostrukturerade och några strukturerade intervjuer samt strukturerade mejlkonversationer och insamling av data. Fokuset låg på att hitta de möjliga effektiviseringsområden i praktiken för att sedan hitta teori och litteratur som belyser de upphittade bristerna. Några teorier som kommer att betonas på grund av deras relevans är Lean, lager- och supply chain teori.

    Studiens resultat och analys visar att utmaningarna som hindrar effektivisering i Coilsterminalen är baserad på interna och externa faktorer. Interna faktorer består av onödig förflyttning av material, omarbetning i kontor och outnyttjat arbetsskift. Externa faktorer orsakas på grund av leverantörer i form av osäkerhet av informationsinput samt material input/output.

    Studien resulterar i att den optimala lösningen är att samarbetet mellan aktörerna i kedjan förbättras så att flöde av information blir bättre och förminska osäkerheten i leverans och utleverans. Vidare uppmuntrar studien Oxelösund Hamn att samla in data, i form av statistik, om dagliga händelser i Stålhamnen så att de belyser problem och kostnader som är dolda. Oxelösund Hamn uppmuntras också införa det outnyttjade arbetsskiftet under natten och förminskning av lagret.

  • 2.
    Antoja Lleonart, Guillem
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    New Generation 4-Channel GNSS Receiver: Design, Production, and Testing2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Due to the current research needs and the lack of commercial multi-channel, multi-constellation GNSS receivers, a two-board solution has been developed so it can be mated with and take advantage of the processing power of the FPGA board branded as MicroZed.

    In order to achieve the proposed goals, an initial phase for assessing and updating the older design, building, and testing of SiGe modules (including both the electronics and casings) has been carried out. The results included demonstrate performances at logging GPS-L1 data with similar C/N0 and AGC values as the previous versions of the modules and offering navigation solutions with accuracies of a few meters. Secondly, a first iteration and design proposal for the new generation receiver has been proposed for GPS and GLONASS L1 and L2, which has been manufactured and tested. Partial tests have been performed due to the flaws of the current revision of the MicroZed Board in regards to its communication peripherals, and the results have validated the receiver’s design provided certain modifications are considered for future iterations. Furthermore, voltage and frequency tests have provided results with an error of less than 7%, and signal tests have provided C/N0 values similar to those of the SiGe modules of around 47[dB-Hz] which will be a useful baseline for future iterations. Finally, a design proposal for an Interface Board used between the older NT1065_PMOD Board and other FPGA boards carrying the standardized FMC connectors has been added to the report and negotiations with manufacturers have been engaged.

  • 3.
    Berezovskaya, Yulia
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Yang, Chen-Wei
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Mousavi, Arash
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zhang, Xiaojing
    Vyatkin, Valeriy
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A hybrid fault detection and diagnosis method in server rooms’ cooling systems2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Data centers as all complex systems are prone to faults, and cost of them can be very high. This paper is focused on detecting the faults in the cooling systems, in particular on local fans level. In the paper, a hybrid approach is proposed. In the approach a model is used as substitute of the real system to generate dataset containing records of both normal and fault cases. On the generated data, machine learning algorithm or ensemble of algorithms are selected and trained to detect the faults. To demonstrate the approach, the rack model of real data center is created, and reliability of the model is shown. Using the model, the dataset with normal as well as abnormal records of data is generated. To detect faults of local fans, simple classifiers are built for all pairs: a local fan – a processor unit. Classifiers are trained on one part of generated data (training data), and then their accuracy is estimated on another part of generated data (test data). A real-time fault detection system is built based on the classifiers. The rack model is used as the substitute of the real plant to check operability of the system.

  • 4.
    Bezerra, Nibia Souza
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Saguna, Saguna
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    de Sousa Jr., Vicente A.
    Federal University of Rio Grande do Norte (UFRN).
    Temperature Impact in LoRaWAN: A Case Study in Northern Sweden2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 20, artikkel-id 4414Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    LoRaWAN has become popular as an IoT enabler. The low cost, ease of installation and the capacity of fine-tuning the parameters make this network a suitable candidate for the deployment of smart cities. In northern Sweden, in the smart region of Skellefteå, we have deployed a LoRaWAN to enable IoT applications to assist the lives of citizens. As Skellefteå has a subarctic climate, we investigate how the extreme changes in the weather happening during a year affect a real LoRaWAN deployment in terms of SNR, RSSI and the use of SF when ADR is enabled. Additionally, we evaluate two propagation models (Okumura-Hata and ITM) and verify if any of those models fit the measurements obtained from our real-life network. Our results regarding the weather impact show that cold weather improves the SNR while warm weather makes the sensors select lower SFs, to minimize the time-on-air. Regarding the tested propagation models, Okumura-Hata has the best fit to our data, while ITM tends to overestimate the RSSI values.

  • 5.
    Booth, Todd
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Critical Infrastructure Network DDoS Defense, via Cognitive Learning2017Inngår i: / [ed] Pietro Manzoni, Universitat Politècnica de València, Spain, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Some public and private services are called part of the Critical Infrastructure (CI), which are considered as the most important services to protect the functioning of a society and the economy.  Many CIs provide services via the Internet and thus cyber-attacks can be performed remotely.  It is now very simple and free to find and download software, which automates performing cyber-attacks.  A recent example is that two teenagers, with close to no security knowledge, created an on-line business. They would run cyber-attacks (online booter service called vDOS, as reported by Brian Krebs) for a small fee. They reportedly earned over 600,000 USD in a short period of time by conducting a large number of automated DDoS cyber-attacks. Then Krebs was retaliated against, and the highest DDoS attack bandwidth ever recorded, 620 Gbps, was launched against Krebs. In this paper we show how cognitive learning can be used to significantly mitigate any effects of DDoS network attacks, against the critical infrastructure.

  • 6.
    Casselgren, Johan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Bodin, Ulf
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Reusable road condition information system for traffic safety and targeted maintenance2017Inngår i: IET Intelligent Transport Systems, ISSN 1751-956X, E-ISSN 1751-9578, Vol. 11, nr 4, s. 230-238Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Driver awareness of current winter road conditions (RCs) is known to affect the frequency of accidents due to sudden changes in these conditions. For example, partially icy roads that appear during autumn in northern areas typically result in collisions and ditch runs unless the drivers are generally aware of the situation. Availing motorists who drive under winter RCs of enhanced information is therefore highly desirable to increase their awareness of hazardous driving conditions. Such conditions need to be predicted ahead of time and presented to drivers before they attempt slippery road sections. Moreover, the identification of slippery RCs should quickly trigger targeted road maintenance to reduce the risk of accidents. This study presents a scalable and reusable collaborative intelligent transport system, herein referred to as an RC information system (RCIS). RCIS provides accurate RC predictions and forecasts based on RC measurements, road weather observations, and short-term weather forecasts. The prediction methods in the context of the distributed RCIS have been tested using a prototype implementation. These tests confirmed that these inputs could be combined into useful and accurate information about winter RCs that can be adapted for different types of users.

  • 7.
    Hasselfors, Victor
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Microtechnology and Nanoscience – MC2, Chalmers.
    Characterization and Modeling of mm-Wave Power Amplifiers2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The next generation of mobile communication (5G) is upon us, and with that newtypes of technologies are needed for improved data rates, reliability, response timeand increased utilization. In this report, two highly efficient linear power amplifiersare characterized and tested with simulated communication signals. The purpose ofthe amplifiers is to be integrated into antenna arrays that will transmit amplifiedcommunication signals to mobile users.One of the amplifiers is tested with modulated communication signals with anoptimized gate bias value. The amplifier shows during the final tests high-efficiencylevels of up to 40% and is still able to behave linearly with>20 dB gain and lowerror vector magnitude below 1%.The fundamental theory for signal processing is described at the beginning of thereport, followed by an overview of the experimental setup built during the thesis formeasuring modulated signals through amplifiers.

  • 8.
    Hägglund, Andreas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Geo-process lookup management2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis presents a method to deploy and lookup applications and devices based on a geographical location. The proposed solution is a combination of two existing technologies, where the first one is a geocode system to encode latitude and longitude coordinates, and the second one is a Distributed Hash Table (DHT) where values are stored and accessed with a $<$key,value$>$ pair. The purpose of this work is to be able to search a specific location for the closest device that solves the user needs, such as finding an Internet of Things (IoT) device. The thesis covers a method for searching by iterating key-value pairs in the DHT and expanding the area to find the devices further away. The search is performed using two main algorithm implementations LayerExpand and SpiralBoxExpand, to scan the area around where the user started the search. LayerExpand and SpiralBoxExpand are tested and evaluated in comparison to each other. The comparison results are presented in the form of plots where both of the functions are shown together. The function analysis results show how the size of the DHT, the number of users, and size of the search area affects the performance of the searches.

  • 9. Jarvis, Dennis
    et al.
    Jarvis, Jaqueline
    Yang, Chen-Wei
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Sinha, Roopak
    Vyatkin, Valeriy
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Janus: A Systems Engineering Approach to the Design of Industrial Cyber-Physical Systems2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The benefits that arise from the adoption of a systems engineering approach to the design of engineered systems are well understood and documented. However, with software systems, different approaches are required given the changeability of requirements and the malleability of software. With the design of industrial cyber-physical systems, one is confronted with the challenge of designing engineered systems that have a significant software component. Furthermore, that software component must be able to seamlessly interact with both the enterprise’s business systems and industrial systems. In this paper, we present Janus, which together with the GORITE BDI agent framework, provides a methodology for the design of agent-based industrial cyber-physical systems. Central to the Janus approach is the development of a logical architecture as in traditional systems engineering and then the allocation of the logical requirements to a BDI (Belief Desire Intention) agent architecture which is derived from the physical architecture for the system. Janus has its origins in product manufacturing; in this paper, we apply it to the problem of Fault Location, Isolation and Service Restoration (FLISR) for power substations. 

  • 10.
    Jonsson, Lars
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    3D modeling of mineshaft using autonomous quad rotor2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this master's thesis a multirotor with the ability to scan its surroundingswas built. To be able to produce these scans the multirotor will be equippedwith a custom built 3D LIDAR. In the future, the scans will be used togenerate a 3D map to visualize mineshafts in a well suited way for inspections.This multirotor is designed with the purpose to map mineshafts that areinaccessible to humans, due to safety reasons. To produce a 3D map of themultirotor surroundings the absolute position is needed. Since the multirotorwill be used in an environment where GPS is unavailable, the positioning issolved by utilizing an IMU and Computer Vision technology with a Rangingdevice.The functionality has been tested in a lab environment resembling real lifeoperational conditions, and conrms that it is possible to use this approachto scan an environment where it is possible to have the multirotor in line-ofsightfor the camera.The 3D scanning is relaying on a stable Wi-Fi connection and absolute positionand as long as this is established it is possible to use this point cloudfor inspection.The positioning of the multirotor is tested up to a range of 40 m, with amaximum measured accuracy of 5 cm, which is well within the range ofthe requirements of the application.

  • 11.
    Kallsäby, Mattias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Modular MiniTest Tester2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    RealTest is a company located in V¨aster˚as, Sweden, that works with embedded systems and test systems. RealTest had a need for a new test system for one of their products, the MiniTester (MT) mk2 that is used to test Drive Control Units (DCUs) used on trains. The problems that had to be solved were, finding out the most common faults of the product, make the test system modifiable and scalable, have a software running on a Windows PC with a working GUI and test logic and design a hardware component measurement unit to generate and measure signals.

    The system described in this report is the software parts of the developed MiniTest tester that runs on a Windows PC as well as the hardware design. The programming of the measurement unit and the testing of that unit is not covered by this report.

    The hardware consist of custom PCBs and Arduino boards. The Windows PC programs implemented a GUI and test logic according to the goals with a few exceptions left for further work. These programs have been evaluated by emulating the hardware. The system is shown to be modifiable in practice by implementation and scalable in theory

  • 12.
    Li, Yuhong
    et al.
    State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing.
    Su, Xiang
    Centre for Ubiquitous Computing, University of Oulu.
    Lindgren, Anders
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Shi, Xinyue
    State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing.
    Cai, Xiang
    State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing.
    Riekki, Jukka
    Centre for Ubiquitous Computing, University of Oulu.
    Distance Assisted Information Dissemination with Broadcast Suppression for ICN-based VANET2016Inngår i: / [ed] Hsu C.-H.,Wang S.,Zhou A.,Shawkat A, Springer, 2016, s. 179-193Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Information-centric networking (ICN) is being applied to the vehicular networks by more and more researchers on account of its lightweight and connectionless networking paradigm and in-network caching characteristics, making it suitable for the dynamic environments of vehicular networks. However, wireless transmission of interest packets to find content in the network may lead to broadcast storms that can affect the performance of information dissemination severely. This paper proposes a distance assisted data dissemination method with broadcast storm suppressing mechanism (DASB) for supporting rapid and efficient information dissemination in ICN-based vehicular ad hoc networks (VANETs). Geo-position data of vehicles are used to accelerate packet forwarding, and vehicular nodes in certain areas are restricted to forward packets in order to suppress the broadcast storm. Simulation results show that the proposed method can greatly reduce the total number of packets transmitted in the network, and the successful information delivery ratio and information delivery time can also be improved

  • 13.
    Li, Yuhong
    et al.
    State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing.
    Wang, Ji
    State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing.
    Lindgren, Anders
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Su, Xiang
    Centre for Ubiquitous Computing, University of Oulu.
    Riekki, Jukka
    Centre for Ubiquitous Computing, University of Oulu.
    Implicit Cooperative Caching based on Information Popularity for Vehicular Networks2017Inngår i: CHANTS 2017: Proceedings of the 12th Workshop on Challenged Networks, co-located with MobiCom 201720 October 2017, New York: ACM Digital Library, 2017, s. 51-56Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Information dissemination is one of the most important tasks of vehicular networks. Therefore, information-centric networking (ICN) technology is being more and more widely used in vehicular networks due to the connectionless and lightweight characteristics of this networking paradigm. Caching plays an essential role in information-centric networks, but current caching techniques for ICN are not ideal for use in vehicular networks on account of the dynamicity and wireless transmission of vehicular networks. This paper presents a caching approach for ICN-based vehicular networks that takes into account both the dynamicity of vehicular networks and the popularity of the information to be distributed. By introducing the “interval” metric and estimating the popularity of information and current networking conditions of the vehicles on road, cooperative caching among nodes can be realized without exchanging cache management information among them. Simulation results show that the proposed approach can increase the storage space utilization and has low data response time for vehicular networks.

  • 14.
    Lindgren, Anders
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Åkerberg, Johan
    Björkman, Mats
    Feasibility of ICN in Automation Networks2017Konferansepaper (Fagfellevurdert)
  • 15.
    Lundberg, Christoffer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    CoFramer: Ett diskussionsformat för djupa diskussioner på publika forum med låg Information Overload inspirerat av Philosophy for Children2019Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Syftet med studien är att presentera ett designkoncept för publika diskussioner på nätet med målet att uppnå djupare diskussioner och minska mängden information overload. Arbetet använder metoden Concept Driven Interaction Design (CDID) som går ut på att skapa ett designkoncept utifrån flera olika teorier som appliceras genom interaktionsdesign. Ett designkoncept innehåller tre delar: ett namn, ett syfte och huvudprinciper. CDID innehåller sju steg som arbetet är utformat efter:

    1.      Concept Generation – Summeras i en tabell som jämför diskussioner i forum (med flera antagande) och diskussioner med hjälp av metoden Philosophy for Children (P4C), samt annan teori.

    2.      Concept Exploration – Åtta olika designaspekter identifieras utifrån jämförelsetabellen.

    3.      Internal Concept Critique – Designaspekterna jämförs med två snarlika diskussionsformat.

    4.      Design of Artifacts – Designkoncept version 1 skapas.

    5.      External Design Critique – Intervjuer utförs för att undersöka intervjupersonerna generella erfarenheter av online diskussioner, testar antagandena från jämförelsetabellen och ge direkt feedback på första versionen av designkonceptet.

    6.      Concept Revisited – Ändringar görs baserat på intervjumaterial och direkt feedback.

    7.      Concept Contextualization – Designkonceptet kopplas tillbaka till litteraturen.

    Studien resulterar i ett designkoncept kallat CoFramer och stödjer dessa huvudprinciper som ställs i kontrast till material som identifierats genom intervjuerna:

    Tabell 1: CoFramers huvudprinciper och faktorer från intervjuer om diskussioner på forum.

    CoFramers huvudprinciper | Från intervjuer om diskussioner på forum

    Strukturerad början och slut | Diskussion utan tydligt slut

    Begränsat antal deltagare | Stor mängd deltagare

    Minimum antal deltagare | Många inaktiva åskådare

    Explicita deltagare | Lite information om deltagare

    Gemensamma förutsättningar | Otydlighet kring deltagares förutsättningar

    Begränsad informationstäthet per inlägg | Långa inlägg och/eller snabba inlägg

    Den röda tråden och parallella trådar | Oftast parallella trådar

    Aktiv samtalsledare | Outredda missförstånd

    Studien indikerar på att CoFramer bör resultera i mer strukturerade diskussioner och som utsätter användaren för en lägre mängd information overload och mindre grounding cost jämfört med vad som vanligtvis uppstår i publika diskussioner online.

  • 16.
    Lyamin, Nikita
    et al.
    Halmstad University, Sweden.
    Kleyko, Denis
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Delooz, Quentin
    University of Liège, Belgium.
    Vinel, Alexey
    Halmstad University, Sweden.
    AI-Based Malicious Network Traffic Detection in VANETs2018Inngår i: IEEE Network, ISSN 0890-8044, E-ISSN 1558-156X, Vol. 32, nr 6, s. 15-21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Inherent unreliability of wireless communications may have crucial consequences when safety-critical C-ITS applications enabled by VANETs are concerned. Although natural sources of packet losses in VANETs such as network traffic congestion are handled by decentralized congestion control (DCC), losses caused by malicious interference need to be controlled too. For example, jamming DoS attacks on CAMs may endanger vehicular safety, and first and foremost are to be detected in real time. Our first goal is to discuss key literature on jamming modeling in VANETs and revisit some existing detection methods. Our second goal is to present and evaluate our own recent results on how to address the real-time jamming detection problem in V2X safety-critical scenarios with the use of AI. We conclude that our hybrid jamming detector, which combines statistical network traffic analysis with data mining methods, allows the achievement of acceptable performance even when random jitter accompanies the generation of CAMs, which complicates the analysis of the reasons for their losses in VANETs. The use case of the study is a challenging platooning C-ITS application, where V2X-enabled vehicles move together at highway speeds with short inter-vehicle gaps.

  • 17.
    Nilsson, Daniel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Evaluation of Secure Long Distance Communication in Non-Urban Environments2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 18.
    Rao, Akhila
    et al.
    SICS Swedish ICT AB, Sweden.
    Schelén, Olov
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Lindgren, Anders
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. SICS Swedish ICT AB, Sweden.
    Performance implications for IoT over information centric networks2016Inngår i: CHANTS '16: Proceedings of the Eleventh ACM Workshop on Challenged Networks, New York: ACM Digital Library, 2016, s. 57-62Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Information centric networking (ICN) is a proposal for a future in-ternetworking architecture that is more efficient and scalable. Whileseveral ICN architectures have been evaluated for networks carry-ing web and video traffic, the benefits and challenges it poses forInternet of Things (IoT) networks are relatively unexplored. In ourwork, we evaluate the performance implications for typical IoT net-work scenarios in the ICN paradigm. We study the behavior of in-network caching, introduce a way to make caching more efficientfor periodic sensor data, and evaluate the impact of presence andlocation of lossy wireless links in IoT networks. In this paper, wepresent and discuss the results of our evaluations on IoT networksperformed through emulations using a specific ICN architecture,namely, content centric networking (CCN). For example, we showthat the newly proposed UTS-LRU cache replacement strategy forimproved caching performance of time series content streams re-duces the number of messages transmitted by up to 16%. Our find-ings indicate that the performance of IoT networks using ICN areinfluenced by the content model and the nature of its links, and mo-tivates further studies to understand the performance implicationsin more varied IoT scenarios.

  • 19.
    Rönnholm, Jesper
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Integration of OPC Unified Architecture with IIoT Communication Protocols in an Arrowhead Translator2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis details the design of a protocol translator between the industrial-automation protocol OPC UA, and HTTP. The design is based on the architecture of the protocol translator of the Arrowhead framework, and is interoperable with all of its associated protocols. The design requirements are defined to comply with a service-oriented architecture (SOA) and RESTful interaction through HTTP, with minimal requirement of the consuming client to be familiar with OPC UA semantics. Effort is put into making translation as transparent as possible, but limits the scope of this work to exclude a complete semantic translation. The solution presented in this thesis satisfies structural- and foundational interoperability, and bridges interaction to be independent of OPC UA services. The resulting translator is capable of accessing the content of any OPC UA server with simple HTTP-requests, where addressing is oriented around OPC UA nodes.

  • 20.
    Sandberg, Oskar
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Nutti, Kenneth
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    CA UIM: Övervakning för Sametingets nätverk2019Independent thesis Basic level (university diploma), 5 poäng / 7,5 hpOppgave
    Abstract [sv]

    Det globala konsultföretaget CGI är leverantör för Sametingets nätverk. Behovet av en förbättrad övervakning på Sametingets nätverk efterfrågades av CGI. Genom att förnya och förbättra övervakningen säkerställs en snabbare felsökning och en högre tillgänglighet. Plattformen som skulle användas för att förverkliga målet heter CA Unified Infrastructure Management (CA UIM).

     

    Eftersom slutprodukten skulle övervaka en skarp miljö så började arbetet med att upprätta en testmiljö där experiment kunde utföras. En liten del av arbetet bestod av att kartlägga det nätverk som skulle övervakas. Det huvudsakliga arbetet gick ut på att lära känna programvaran. UIM bygger på att prober utför insamling av data som sedan transporteras vidare till en gemensam databas för den specifika domänen. Databasen kan i sin tur leverera data till exempelvis dashboards på front-end sidan. 

    Följande prober har använts i vårt arbete:

    • Net_Connect – Använder ICMP för att bekräfta en enhets tillgänglighet.

    • Interface_Traffic - Övervakar nätverkstrafiken med SNMP-agenter.

    • CDM - Ansvar för övervakningen av CPU, disk och minnesutnyttjande på servrar.

     

    Efter att designen av våra dashboards var färdigställda och övervakningen fungerade så gick vi över till den skarpa miljön och upprättade samma koncept där. Arbetet presenteras sedan för CGI i Kiruna med positiva reaktioner.

  • 21.
    Svensson, Philip
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Översikt av nätverk på LEAB: analys, uppdatering av dokumentation och förbättringsförslag2019Independent thesis Basic level (university diploma), 5 poäng / 7,5 hpOppgave
  • 22.
    Tiainen, Arttu
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Inter-Satellite Link Antennas: Review and The Near Future2017Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave
    Abstract [en]

    The emerging trend in distributed spacecraft systems of using multiple spacecraft which share functions as opposed to independent spacecraft has given opportunities for missions previously infeasible. Inter-satellite link (ISL) communications provide a direct link within the space segment without need of an intermediate ground segment to relay the data. As the distributed spacecraft systems (DSS) have become less exotic and more complex, the need and demand for inter-satellite antenna systems has increased and the requirements for the antenna systems more diverse and become more demanding. This document is a research of the antennas currently used for ISL, already flown or will be launched in the near future. While the emphasis is strongly in the antennas, the other parts of the ISL communications sub-systems are observed. To limit the scope of the work, optical cross links are not observed in this document. ISL used only for very close proximity, such as several kilometres, are given only limited scope as the main challenges on those do not involve antennas. Furthermore, the major emphasis is given to systems which can be seen as commercially important. This document is divided in five main sections and the conclusions. In the first section the features and the challenges of ISLs are described. In the second section a parametrisation system for antennas is defined and this system is used in following sections to describe the ISL sub-systems and antenna used in them. The third part is a survey of recently flown space missions with ISLs. The fourth section is a survey on the missions which are scheduled to fly in near future and a brief survey of the solutions offered by satellite service providers and manufacturers. Due to the limited technical data available, the fourth section contains far more reverse engineering and assumptions than the survey on legacy missions. The fifth section describes the several families of ISL suitable antennas under development and discusses about several topics which relate to the ISL antenna development. In this part also are defined several example antenna specifications and the applications of those. The study concludes that antennas suitable for inter-satellite links are not inherently different from ground segment communication antennas of the S/C. The major difference is the need for greater coverage, which can be attained by multiple antenna elements, beam steering or antenna pointing. Specific considerations are needed to be taken into account and often the use of ISLs will increase the technical challenges, but it can provide solutions for problems which cannot be solved otherwise.

  • 23.
    Toufanpanah, Monir
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Decision Support framework: Reliable Federated Single Sign-on2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Identity management is a critical concept for enterprises, and it has turned to more challenging issue since businesses are significantly moving towards service oriented architecture (SOA) with the aim to provide seamless service delivery to their customers, partners and employees. The organizational domains are expanded to blur the virtual borders, simplify the business collaboration and maximize opportunities in the competitive market place, which explicitly shows the essentiality for federating the identities. Real-world identity comprises of different dimensions such as Law, Business, Policy, Technology and Society, therefore reliable digital identity management and successful federation are required to take these dimensions and complexity into consideration.

    Considering variety of academic and industrial researches that report on remarkable demands for identity federation adoption by enterprises, this study has approached federated Identity Management from technological point of view. Technologies provide tools and mechanisms to satisfy the business requirements and enable single sign-on capability in reliable federated platform.

    Different authentication technologies and standards have emerged to enable federated single sign-on (FSSO) implementation as a core service of the FIdM, each with different features and capabilities. This brings more complexity and confusion for experts and decision makers for FIdM adoption and development. To overcome this obstacle and accelerate the data collection and analysis process for decision makers, this research contributes to the filed by providing a conceptual framework to simplify the analysis of underlying technology for decision making process. In this framework 1) a list of state-of-the-art requirements and mechanisms for successful identity federation and reliable SSO is elaborated, 2) Six most prevalent standard authentication technologies along with latest specifications are analysed, explained and assessed against the defined criteria, and 3) several security and privacy consideration are gathered. The usage of framework is monitored and the efficiency of it is evaluated in 2 real business case scenarios by five IT experts and the result is reported.

  • 24.
    Yang, Chen-Wei
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Cyber-Physical Engineering of Distributed Automation Systems in Energy Domain2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main focus of this thesis is in the domain of Energy Systems, specifically in the engi-neering of modern Smart Grid (SG) automation systems. The SG has been categorizedas a Cyber-Physical System (CPS), a complex system which exhibits tight integration between the cyber and the physical processes and their interactions in a networked envi-ronment. The complexity and the computation of the automation system are expectedto increase with the promise of a ”smart” electric grid which is capable of self-healing, self-reconfiguration and become more resilient against cyber-attacks. These automation software systems require control strategies which are distributed in execution and requirevery tight integrations and interactions between various modular software and hardware components. As the automation system becomes more software intensive, we hypothesizethat existing design practices of developing the substation automation software system would struggle to cope with the distributed design challenges of the Smart Grid and they could be substantially enhanced by the application of model-driven design, distributed software architectures and semantic models.

    Model-driven engineering (MDE) is a software design paradigm that leverages the use of abstraction models at different stages of the design process for engineering complex software systems. MDE is widely used in the software engineering domain and it has proven to be effective when designing and maintaining large-scale software applications.One of the core tenants of MDE is model transformation and it is considered the heartand soul of MDE. The standard modelling language that is used for MDE in software engineering is the Unified Modelling Language (UML), which is a visual language with awide array of tool support. Despite its popularity in the software domain, UML models still have its limitations. In particular, the lack of uniformed semantics between its 13different visual diagrams and the lack of formal notations. In this thesis, we proposethe Cyber-Physical Engineering (CPE) framework, an MDE framework which combines semantic models and MDE based automatic model transformation in order to auto-generate both the automation control system and the simulation plant model from thephysical and functional specifications of CPS systems.

    All the scientific papers included in this thesis contributes towards the proposed Cyber-Physical Engineering methodology which includes MDE using semantic models, formal modelling of functional requirements and co-simulation testing of CPS systems.

    The contribution of the thesis is fivefold. Firstly, the thesis proposes the CPE frame-work, which is based on the use of semantic web modelling language where logical rea-soning can be applied to the models. The modelling language that is used is the Web Ontology Language (OWL), which is a declarative language with a strong formal foun-dation based on description logic. Secondly, the extended Semantic Web Rule Language(eSWRL) is introduced which defines the constructors that are necessary for model trans-forming OWL ontology models. The eSWRL transformation language is proposed to bean extension to the widely used ontology reasoning language Semantic Web Rule Lan-guage (SWRL) in order to address the limitations of monotonicity which restricts SWRLfrom transforming ontological models. Thirdly, the implementation of the underlying transformation engine of eSWRL in SWI Prolog. Fourthly, the formal modelling of func-tional requirements in ontology is proposed which investigates the viability of using nat-ural language based functional requirements to add control flow to the auto-generated automation control system. Lastly, an automated script based co-simulation environ-ment is shown to demonstrate how black-box validation can be performed to test theauto-generated automation control system.

    Finally, the thesis presents the resultant CPE framework for the modelling and genera-tion of distributed CPS automation software that leverages the use of semantic web OWL models. It is aimed to provide a top-down design approach of developing distributed con-trol software for CPS systems along with the simulation model of the physical plant. Inthis thesis, we demonstrate the development process of the CPE framework and throughcase study applications, how a semi-complete distributed automation software system in IEC 61499 can be automatically generated from substation specifications in IEC 61850 and natural language based functional requirements which provide the structure and thecontrol flow of the distributed automation software respectively. An eSWRL toolchainhas been developed to facilitate the various model transformation process of the CPE framework.

  • 25.
    Yang, Chen-Wei
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Dubinin, Victor
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. Penza, Penza region Russian Federation.
    Vyatkin, Valeriy
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Automatic Generation of Control Flow from Requirements for Distributed Smart Grid Automation Control2019Inngår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Smart grid is a Cyber-Physical System with a high level of complexity due to its de-centralized infrastructure. IEC 61850 and IEC 61499 are two industrial standards which can address the challenges introduced by the Smart Grid on the substation automation level. Development of Smart Grid automation software is very time consuming process due to the need to address many requirements and high degree of customisation in every new substation. This limits the adoption of such smart grid technologies as digital substation. This paper aims at addressing this limitation by applying a semi-formal boilerplates model of functional requirements originally presented in informal natural language. The boilerplates are then modelled formally in an ontology for MDE model transformation. The contribution of this paper is the development of the semi-formal and formal boilerplate representation in the form of ontology to formulate Smart Grid requirements and demonstrating how functional requirements can be translated to IEC 61499 control codes using MDE to auto-generate an IEC 61499 PAC control system with structure and control flow. The MDE framework augmented with the requirements models is illustrated on a case study from CIGRE representing different stages of modelling in the proposed framework.

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